Filey FAS

Presentation to Planners

Stewart Rowe

15.2.2016

23 September 2015

History of Flooding

There is a long history of flooding in Filey

caused by extreme rainfall events.

These rainfall events have resulted in widespread overland flooding, overwhelming of watercourses and the urban drainage system, localised ground instabilities, and damage to properties across the town.

There are records of properties flooding from 1985 onwards. The most significant flooding occurred in October 2000, August 2002, and July 2007.

The total cost of repair works for the 2002 event was estimated at approximately £3 million.

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23 September 2015

July 2007 Event

Over 80mm of rain fell in just one and half hours, with the

water reported to be waist deep in places. Significant damage and disruption occurred, including:

• 8 people had to be rescued from the swimming pool at Filey School

• Filey inshore lifeboat was used within the town to rescue people stranded in their homes

• Over 30 people had to be evacuated from their homes and an emergency centre was set up in the Evron Centre and Trinity Church

• Classrooms, swimming pool, and other buildings were flooded at Filey School, closing it for a short period

• Both main roads into Filey (Muston Road and Scarborough Road) were closed at one stage of the flood;

• North Yorkshire Fire Service received over 150 calls in five hours seeking help

• Over 200 homes were affected by internal flooding; • The cost of the remedial work after the event was

estimated at approximately £6.4 million.

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23 September 2015

Background to Scheme

Since the major flood events of 2002 and 2007 various investigations and studies

looking into the causes of the flooding and the potential solutions have been carried

out.

These have confirmed that the flooding in Filey is caused by the complex interaction of

overland flows from the catchment surrounding the town, the surface water runoff

within the town, and the urban drainage system.

The solution to the flooding has therefore needed a multi-agency approach. The

Project Steering Group was set up to help the partnership working and includes

representatives from:

Scarborough Borough Council

Filey Town Council

North Yorkshire County Council

Environment Agency

Yorkshire Water

Filey Flood Working Group

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23 September 2015

What have we been doing ?

A staged approach has been adopted to progressively refine

the scheme and get a better understanding of the risks,

eliminate them where possible, and provide an affordable

solution to the flooding problems in Filey.

Existing data and previous reports have been reviewed to

identify gaps in knowledge and help focus the activities at

each stage of the project.

Ground level information has been collected both from

the air (Lidar) and on the ground (topographic survey).

This feeds into the flood mapping and design of the

scheme to identify the best locations for the defences and

accurately determine the height they need to be.

Detailed numerical modelling of the catchment has been

carried out to determine the flow paths, flood extents and

depths, and the volumes of water needing to be stored by

the scheme.

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23 September 2015

What have we been doing ?

Ground investigation to find out what the

ground is made of to determine whether the

material to be excavated from the storage

areas is suitable to be used for building the

embankments and to identify any potential

contaminations.

Archaeological surveys including Ground

Penetrating Radar (GPR) to check for the

presence of any historical remains.

Consultation with stakeholders and landowners

to help refine the locations of the defences.

Developing the scheme concept to produce

detailed designs of each section of the

scheme, finalising the locations and sizes of

the defences needed.

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23 September 2015

What have we been doing ?

We have carried out a range of surveys in order to enhance our understanding of the existing environment within the study area. This provides the baseline against which the scheme is assessed to identify potential environmental impacts. The surveys which have been carried out include:

• Phase 1 habitat survey and targeted protected species surveys, including bats, badgers, water voles, and great crested newts;

• Baseline noise survey; • Ground investigation with collection of soil samples for laboratory analysis; • Geophysical survey for archaeology; and, • Site walkovers in order to determine viewpoints to the scheme from the

surrounding areas.

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23 September 2015

What works are we proposing?

The urban centre of Filey is located in a low spot

surrounded by rising agricultural land creating a

bowl shaped catchment. The topography of the

surrounding land directs surface water runoff

towards the town

Historically this runoff would have discharged

directly to the sea via ravines. However these

have been culverted as the town of Filey has

developed

There are currently no formal flood defences in

place & although Yorkshire Water has carried out

work to improve the existing urban drainage

system, surface water flooding remains a major

issue.

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23 September 2015

What works are we proposing?

The proposed scheme comprises:

A series of earth embankments to encircle larges areas

of the town

Storage areas at specific locations to temporarily store

floodwater before it is released at a controlled rate into

the existing urban drainage system and ravines once

the storm has passed.

Land raising

Drainage channels and culverts to redirect floodwater

flows ditches.

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23 September 2015

What works are we proposing?

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23 September 2015

Area 1 – Parish Fields

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23 September 2015

Area 2 – Sycamore Avenue

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23 September 2015

Area 3 - Wharfedale

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Corner of field raised by 0.5m at field boundary (approx.) to redirect water into new channel

0.5m high embankment (approx.)

1.5m deep channel (approx.)

Embankment ends at 42.0m AOD contour line

0.5m high embankment (approx.)

1.0m deep channel (approx.)

Gap in the embankment to allow water from school playing fields to drain into new channel

CULVERT 2

CULVERT 1 - Section of new channel culverted to provide footpath crossing

Corner of field raised by 0.5m at field boundary (approx.) to redirect water into new channel

0.5m high embankment (approx.)

1.5m deep channel (approx.)

Embankment ends at 42.0m AOD contour line

0.5m high embankment (approx.)

1.0m deep channel (approx.)

Gap in the embankment to allow water from school playing fields to drain into new channel

CULVERT 2

CULVERT 1 - Section of new channel culverted to provide footpath crossing

23 September 2015

Embankment Details

The embankments will be between 0.5m and 1.5m high, and therefore small enough

for most people to be able to see over them. They will have gently sloping sides so that

they blend in to the surrounding rural landscape.

Constructed from the material excavated to from the channels and flood storage areas.

This reduces the amount of material which will need to be disposed of off-site and also

reduces the need to import material to build the embankments, keeping the costs of

the scheme down.

Finished with topsoil, which will be removed from underneath the footprint of the

embankments before they are constructed and reused. The topsoil will be seeded with

grass so that the embankments will become green and blend in with the surrounding

rural landscape.

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23 September 2015

Channel Details

The channels will be between 0.5m and 2.5m deep. They will have gently sloping sides so that they blend in to the surrounding rural landscape.

The material excavated from the channels will be used to construct the embankments. This reduces the amount of material which will need to be disposed of off-site and also reduces the need to import material to build the embankments, keeping the costs of the scheme down.

Finished with topsoil, which will be removed from the top width of the channels before they are excavated and reused. The topsoil will be seeded with grass so that the channels will become green and blend in with the surrounding rural environment.

In normal weather conditions the channels should mainly be dry; they will only contain water during storm events as they catch the overland flows and divert them away into the new flood storage areas and Long Plantation Watercourse.

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23 September 2015

Storage Area Details

Storage Area A will be approximately 250m long by 130m wide, with a maximum

depth of approximately 2m. It will be excavated below the existing ground level.

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23 September 2015

Storage Area Details

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Storage Area B will be approximately 185m long by 50m wide, with a maximum depth

of approximately 2m.

Storage Area C will be approximately 115m long by 60m wide, with a maximum depth

of approximately 1.5m.

23 September 2015

Environmental Aspects

An EIA has been undertaken to consider the impacts of the proposed

scheme on :

• Habitats and protected species • Soils, hydrogeology and hydrology • Birds • Air quality • Noise and vibration • Soils and land use • Archaeology and cultural heritage • Landscape and visual • Socio-economic • Tourism and recreation The assessment work carried out to date has not identified any significant environmental impacts. Potential for enhanced habitat for birds and improvements to landscape character due to reinforcement of hedgerows and establishment of more diverse planting

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23 September 2015

Consultation

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There has been consultation carried out historically with the public,

landowners, interested parties, and statutory consultees following the

major flood events and during the previous studies and stages of the

scheme.

As part of the design development stage of the scheme we have

consulted with interested parties including:

• Regular monthly progress meetings with the Project Steering

Group

• Provided information for the newsletters distributed to residents by

the Filey Flood Working Group

• Presentations to and discussions with affected landowners

• Discussions with Natural England on environmental aspects

• Site visit and discussions with Filey Bird Observatory and Group

• Discussions with various departments in Scarborough Borough

Council and North Yorkshire County Council, including the County

Archaeologist

• Various press releases to local and regional press and local radio

stations

• Responses to correspondence received from members of the

public

• Development of a project website:

http://fileyfloodalleviationscheme.wordpress.com

23 September 2015

How it Works – North Area – Without Scheme

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23 September 2015

How It Works – North Area – With Scheme

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23 September 2015

How It Works – South Area – Without Scheme

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23 September 2015

How It Works – South Area – With Scheme

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23 September 2015

Scheme Benefits

The proposed scheme is in direct compliance with the aims of the Filey Town Plan

which identifies the need for a flood alleviation scheme.

129 residential and 94 non-residential properties will immediately benefit from the

scheme in a 100yr event (1% annual probability event).

With the impacts of climate change by 2085 there will be 353 residential and 97 non-

residential properties benefitting from the scheme in a 100yr event (1% annual

probability event).

Disruption to Filey School caused by flooding will be avoided, meaning the school will

no longer need to be closed and pupil’s education will not be disrupted.

Reduced risk to life during flood events for residents, which is particular issue in Filey

due to type of housing (i.e. lot of bungalows) and vulnerability of the population (i.e.

age and long term health problems)

There may be some reduction in disruption to transport (roads and railway), through

reduced flood depths, durations, and lengths of road and railway track affected.

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23 September 2015

Scheme Benefits

The Present Value benefits of the

scheme over 100 years are £20.4M.

This includes:

Direct property damages avoided

Evacuation costs avoided

Vehicle damages avoided

Emergency services costs avoided

(for responding to flood events)

Health benefits (e.g. reduction in

stress for residents)

School disruption avoided

Risk to life benefits

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23 September 2015

ANY QUESTIONS ?

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